Research Article

Two-photon polymerization of polyethylene glycol diacrylate scaffolds with riboflavin and triethanolamine used as a water-soluble photoinitiator

JUNC/NCSU Joint Department of Biomedical Engineering, University of North Carolina, Campus Box 7575, Chapel Hill, NC 27599-7575, USA

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Shaun D Gittard

Nanotechnology Department, Laser Zentrum Hannover e. V., Hollerithallee 8, D-30419 Hannover, Germany

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Anastasia Koroleva

Nanotechnology Department, Laser Zentrum Hannover e. V., Hollerithallee 8, D-30419 Hannover, Germany

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Sabrina Schlie

Nanotechnology Department, Laser Zentrum Hannover e. V., Hollerithallee 8, D-30419 Hannover, Germany

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Arune Gaidukeviciute

Nanotechnology Department, Laser Zentrum Hannover e. V., Hollerithallee 8, D-30419 Hannover, Germany

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Boris N Chichkov

Nanotechnology Department, Laser Zentrum Hannover e. V., Hollerithallee 8, D-30419 Hannover, Germany

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Roger J Narayan

* Author for correspondence

JUNC/NCSU Joint Department of Biomedical Engineering, University of North Carolina, Campus Box 7575, Chapel Hill, NC 27599-7575, USA.

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Email the corresponding author at roger_narayan@ncsu.edu

Published Online:22 Oct 2013https://doi.org/10.2217/rme.13.60

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Abstract

Aim: In this study, the suitability of a mixture containing riboflavin (vitamin B2) and triethanolamine (TEOHA) as a novel biocompatible photoinitiator for two-photon polymerization (2PP) processing was investigated. Materials & methods: Polyethylene glycol diacrylate was crosslinked using Irgacure^® 369, Irgacure 2959 or a riboflavin–TEOHA mixture; biocompatibility of the photopolymer extract solutions was subsequently assessed via endothelial cell proliferation assay, endothelial cell viability assay and single-cell gel electrophoresis (comet) assay. Use of a riboflavin–TEOHA mixture as a photoinitiator for 2PP processing of a tissue engineering scaffold and subsequent seeding of this scaffold with GM-7373 bovine aortic endothelial cells was also demonstrated. Results: The riboflavin–TEOHA mixture was found to produce much more biocompatible scaffolds than those produced with Irgacure 369 or Irgacure 2959. Conclusion: The results suggest that riboflavin is a promising component of photoinitiators for 2PP fabrication of tissue engineering scaffolds and other medically relevant structures (e.g., biomicroelectromechanical systems).

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Papers of special note have been highlighted as: ▪ of interest ▪▪ of considerable interest

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Vol. 8, No. 6

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Published online 22 October 2013

Published in print November 2013

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Financial & competing interests disclosure

This work was supported by the Deutsche Forschungsgemeinschaft (DFG), the Cluster of Excellence REBIRTH, SFB TR 37, and the US National Science Foundation (Grant 0936110). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

The authors state that they have obtained appropriate institutional review board approval or have followed the principles outlined in the Declaration of Helsinki for all human or animal experimental investigations. In addition, for investigations involving human subjects, informed consent has been obtained from the participants involved.

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